Java 常用集合间的相互转化（Array/List/Set）

Set转化成List

Map<String, List<Ress>> result = ressDao.getPieChartData();
List<String> domains = new ArrayList<String>(result.keySet());

List转化成Set

Set set=new HashSet(new ArrayList());

 

 

Set/List转化成Array，只需Object.toArray()即可.

 

Array转化成Set/List

String[] array = {"A", "B", "C"};    
List list = new ArrayList();    
Set set = new HashSet();    
CollectionUtils.addAll(list, array);    
CollectionUtils.addAll(set, array);